These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Serial reconstructions of granule cell spines in the mammalian olfactory bulb.
    Author: Woolf TB, Shepherd GM, Greer CA.
    Journal: Synapse; 1991 Mar; 7(3):181-92. PubMed ID: 1882328.
    Abstract:
    The morphology of olfactory bulb granule cell spines and their dendrodendritic synaptic relations with mitral and tufted cell dendrites were examined using serial electron micrographs and 3D computer reconstructions. Most granule cell spines were pedunculated with large elliptical heads and necks (stems) longer than those described for exclusively postsynaptic spines elsewhere in the nervous system. The spines typically contained a mitochondrion, which most likely reflects the metabolic requirements of the presynaptic functions of these spines. In several cases multiple spine heads were observed connected to the parent dendritic trunk via a common neck. In addition, dendritic varicosities making synaptic connections were noted. In the data set sampled, all of the reconstructions supported the hypothesis of divergence of granule cell connectivity: in no instance was a granule cell found to contact repeatedly the same mitral or tufted cell dendrite. Examination of the topological organization of reciprocal dendrodendritic synaptic connections with mitral/tufted cell dendrites revealed parallel rows of spine heads on mitral/tufted secondary dendrites separated by intervening zones of several microns in which no synaptic appositions were found. The results provide evidence regarding rules of connectivity underlying the function of local circuits in mediating lateral inhibition in the external plexiform layer of the olfactory bulb.
    [Abstract] [Full Text] [Related] [New Search]